Low-cost roller-type photographic fluid spreading apparatus

ABSTRACT

Apparatus for spreading processing fluid between a pair of sheet materials and adapted to be inserted into and removed from a camera as an integral assembly. A pair of rollers are rotatably mounted between spaced apart bearing blocks which serve to establish a predetermined minimum spacing between the facing surfaces of the rollers and to permit a limited amount of displacement of one of the rollers away from the other. U-shaped spring elements associated with each bearing block serve to resiliently urge the rollers toward each other. The rollers, bearing blocks and spring elements are mounted on a platform member, preferably formed of a single piece of molded plastic material, which includes a spring latch for releasably retaining the apparatus in the camera, an arrangement for facilitating the assembly of the load springs into their operative positions, a support surface and bridge for guiding the sheet materials between the rollers and an arrangement for resiliently mounting an edge control bar in operative relationship with its bridge.

[ July 17, 1973 LOW-COST ROLLER-TYPE PHOTOGRAPHIC FLUID SPREADING APPARATUS lnventors: Herbert A. Bing, Wayland;

Christopher Brayton, Needham; Leon Rubinstein, Natic, all of Mass.

[73] Assignee: Polaroid Corporation, Cambridge,

Mass.

[22] Filed: July 7, 1971 [21] Appl. No.: 160,364

[52] US. Cl. 95/89 R, 95/13 [51] Int. Cl. G03b 17/52 [58] Field of Search 95/13, 89

[56] References Cited UNITED STATES PATENTS 2,056,584 10/1936 Murck 95/94 R 3,053,160 9/1962 Bachelder et a1 95/13 X 3,165,039 l/1965 Downey 95/13 3,364,834 l/1968 Erikson.... 95/89 R 3,498,196 3/1970 Finelli 95/13 3,511,152 5/1970 Erlichman 95/13 3,561,340 2/1971 Erliehman 95/13 3,589,262 6/1971 Chen 95/13 3,590,707 7/1971 Merz 95/13 2,722,871 11/1955 Whittier 95/89 R I M ssmam? Primary Examiner-Samuel S. Matthews Assistant Examiner-:Alan Mathews [57] ABSTRACT Apparatus for spreading processing fluid between a pair of sheet materials and adapted to be inserted into and removed from a camera as an integral assembly. A pair-of rollers are rotatably mounted between spaced apart bearing blocks which serve to establish a predetermined minimum spacing between the facing surfaces of the rollers and to permit a limited amount of displacement of one of the rollers away from the other. U- flmaed a na dementsasseiaisith as b a block serve to resiliently urge the rollers toward each other. The rollers, bearing blocks and spring elements are mounted on a platform member, preferably formed of a single piece of molded plastic material, which includes a spring latch for releasably retaining the apparatus in the camera, an arrangement for facilitating the assembly of the load springs into their operative positions, a support surface and bridge for guiding the sheet materials between the rollers and an arrangement for resiliently mounting an edge control bar in operative relationship with its bridge.

24 Claims, 7 Drawing Figures LOW-COST ROLLER-TYPE PHOTOGRAPHIC FLUID SPREADING APPARATUS BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to photography and, more particularly, to improved apparatus for distributing processing fluid in a layer between a pair of superposed sheet materials.

2. Description of the Prior Art Cameras of the self-developing type generally employ a pair of spreader elements which facilitate the formation of a visible image in a photographic sheet by a diffusion-transfer process. In a typical arrangement, a sheet of photosensitive material is first exposed to image-carrying light rays to form a latent image therein. This sheet is subsequently progressively pressed against an image-receiving sheet with a predetermined quantity of a viscous processing fluid being disposed there between. In this respect, the fluid may initially be releasably stored in a rupturable pod or container attached to one of the photographic sheets. As the assembly, comprising such sheets and pod, is advanced between a pair of spreader elements, those members exert a compressive force thereon that first ruptures the pod and subsequently spreads the fluid released therefrom as a layer between the superposed sheets. The spreader elements themselves may typically comprise either a pair of rollers, one roller and a rigid non-rolling member, or a pair of rigid non-rolling members.

The fluid spreading process is a critical consideration in producing high-quality photographic prints by a diffusion-transfer process. Much effort was required to develop, engineer and manufacture the film units and spreader elements employed in the self-developing cameras currently being marketed. The quality of the finished print provided by these photograohic systems is directly related to the nature of the fluid coating applied to the photographic sheets. In general, the lower the pull-force required to advance the superposed sheet materials between the spreader elements, the more uniform or smooth will be the advance of those sheets through the spreader system. Obviously, the quality of the finished print improves as a function of the uniformity with which the processing fluid is spread between the photographic sheets.

In order to reach the mass amateur market, it is necessary that the cost of self-developing cameras be kept to an absolute minimum. More specifically, a major goal in the self-developing camera art is the development of a camera which can be marketed at substantially the same price as a conventional-type camera of an equivalent quality. This is not a simple task when one realizes that such cameras must perform all the functions of the more conventional-type cameras, and additionally include a film processing capability.

Along these lines, experience has shown that the fluid spreading apparatus necessarily incorporated in selfdeveloping cameras represents a significant cost element. Traditionally, in commercially available systems, this apparatus comprised a pair of precision machined stainless steel rollers and a mounting arrangement therefor which facilitated their proper operation and frequent cleaning. In order to provide a lower-cost fluid spreading apparatus for its Big Swinger and Color Pack cameras which are produced for the very moderately priced amateur market, the Polariod Corporation of Cambridge, Massachusetts developed the spreader system described in detail in US. Pat. Nos. 3,485,155; 3,499,373; 3,498,196 and 3,537,371. This apparatus comprises a pair of relatively inexpensive non-rolling fluid spreader members formed of sheet metal parts. As is well known, millions of these Big Swinger and Color Pack cameras have already been sold utilizing this particular low-cost fluid spreading system. It is selfevident that photographs produced employing such apparatus have proven quite satisfactory. However, this particular low-cost spreader system constituted a compromise to the extent that the pull-force required to advance the photographic sheet materials between its non-rolling spreader members was somewhat greater than that required to-advance such sheet materials between the more traditional prior art roller-type spreading systems. The ultimate goal therefore still exists, i.e., the development of a fluid spreading system of absolute minimum cost which does not compromise the quality of the photograph furnished to the user.

An object of this invention, therefore is to provide improved photographic apparatus for spreading a processing fluid as a layer between sheets of material.

An important object of this invention is to provide an extremely lowcost fluid spreading apparatus employing a pair of rollers.

Another object of this invention is to provide apparatus of the type indicated which may be inserted into and removed from cameras of the self-developing type as an integral assembly.

A further object of this invention is to provide apparatus of the type indicated which may be utilized to replace fluid spreading apparatus currently employed in commercially available cameras without requiring any alterations to be made to other elements of such cameras.

An additional object of this invention is to provide apparatus of the type indicated which may be fabricated in relatively inexpensive assembly operations.

SUMMARY OF THE INVENTION In its illustrated embodiments, the fluid spreading apparatus of this invention has been depicted as being employed in a self-developing camera produced by the Polariod Corporation of Cambridge, Massachusetts and identified as their Colorpack II camera, i.e., as replacing the fluid spreading system initially incorporated and marketed in that camera.

A pair of rollers are rotatably supported between spaced apart bearing blocks. In this connection, one of the rollers is fixedly positioned between the bearing blocks against translational motion while the other is mounted in slotted recesses of the respective blocks so as to establish a predetermined minimum spacing between the sheet contacting facing surfaces of the rollers and, at the same time, to permit a limited amount of movement of one of the rollers in a direction away from the other roller. Supported on each bearing block is a U-shaped spring element which continually urges respective ends of the rollers towards each other. The facing surfaces of the rollers extend a distance substantially equal to the width of the photographic sheet materials and terminate at a point spaced from adjacent sections of the bearing blocks. In this manner any fluid escaping from between the superposed sheet materials as they pass between the rollers will not collect on the facing surfaces themselves.

The platform member, preferably formed of a single piece of molded plastic material, serves to support and retain the roller-bearing block-load spring elements. This platform member also includes guide and ramp means for facilitating the operative positioning of the load springswith respect to the bearing blocks and rollers during assembly operations. Complementary recess and detent means provided on the springs and bearing blocks serve to releasably retain the springs in their operative positions.

The platform member also includes a spring latch, which cooperates with a brace in the camera to releasably retain the fluid spreading apparatus in the camera, and stops for limiting movement of the spring latch to preclude overstressing of same. Importantly, the platform member further includes a bridge and a support surface, which serve to guide the photographic sheet materials between the rollers, and an edge control bar resiliently mounted on the platform member cooperates with adjacent portions of the bridge to preclude fluid from escaping from between the longitudinal edges of the superposed sheet materials as they pass through the rollers.

In one illustrated embodiment, one end of each load spring element seats on a support surface of its respective bearing block while its other end initially seats against a portion of one of the rollers. In a second illustrated embodiment, both ends of each load spring element are initially seated against support surfaces of its respective bearing block.

BRIEF DESCRIPTION OF THE DRAWINGS The novel features that are considered characteristic of the invention are set forth with particularity in the appended claims. The invention itself, however, both as to its organization and its method of operation, together with additional objects and advantages thereof, will best be understood from the following description of the preferred embodiments when read in connection with the accompanying drawings wherein like numbers have been employed in the different figures to denote the same parts and wherein:

FIG. 1 is a diagrammatic perspective view of a selfdeveloping camera embodying features of this invention;

FIG. 2 is an exploded diagrammatic perspective view of the fluid spreading apparatus employed in the camera illustrated in FIG. 1;

FIG. 3 is a diagrammatic perspective view of the fluid spreading apparatus employed in the camera illustrated in FIG. 1 with certain portions of that apparatus being shown in phantom; V

FIG. 4 is a diagrammatic bottom plan view of the fluid spreading apparatus shown in FIG. 2 with certain parts thereof being shown in phantom;

FIG. 5 is a fragmentary sectional view of the fluid spreading apparatus taken generally along line 5-5 of FIG. 1 at such time as a pair of photographic sheets are being advanced therethrough;

FIG. 6 is a fragmentary diagrammatic sectional view of the fluid spreading apparatus of FIG. 2 illustrating the initial relationship between one of its load springs and a roller thereof; and

FIG. 7 is a view similar to FIG. 6 illustrating a different embodiment of the fluid spreading apparatus of this invention.

DESCRIPTION OF A PREFERRED EMBODIMENT As indicated, in its illustrated embodiments, the present invention is depicted as forming part of a selfdeveloping camera 10. More specifically, the camera 10 diagrammatically illustrated in FIG. 1 of the drawings compromises an aforementioned Colorpack II" camera produced by the Polaroid Corporation of Cambridge, Massachusetts with its original fluid spreading system or apparatus replaced by the fluid spreading system or apparatus 12 of the present invention.

As shown in that figure of the drawings, the camera 10 is basically constituted by a main camera body 14 to which a back body member 16 is pivotally connected. When the back body member 16 is disposed in its open position with respect to the main camera body 14, access is provided into the interior of the camera 10 for purposes of loading the camera with a film pack (not shown) containing a sufficient quantity of photographic materials to produce a plurality of reflective photographic prints. These film packs may, for example, be identical to those currently marketed by the Polaroid Corporation of Cambridge, Massachusetts and identified as Land Pack Film Type 107 (black-andwhite film) or Polacolor Land Film Type 108 (fullcolor film). Each of these particular film packs contains a plurality of eight film units. As is well known, in order to produce a reflective print, each film unit contains a relatively thick, stifi' sheet of image-receiving material 18, a relatively thin, flexible sheet of photosensitive image-recording material 20 and a rupturable pod (not shown) of processing fluid 22 (See FIG. 5). Additionally, each such film unit includes other components not illustrated in the drawings such as a mask, a bib, a leader, a tab, traps and a pair of rails respectively positioned along the longitudinal edges of one of the photographic sheet materials.

Forming part of the main camera body 14 is a lens and shutter housing 24. This housing 24 is mounted at the outer end of a light-tight sleeve 26 which serves to fixedly position the cameras lens 28 a predetermined distance from the cameras film plane and to provide a light-tight optical path therebetween. Attached at one side of the main camera body 14 is a rangefinderviewfinder 30 that has been shown in phantom so as not to obstruct the view of certain other portions of the camera 10. After an aforementioned film pack has been loaded into the camera 10, the cameras back body member 16 may be pivoted to its closed position where it cooperates with the main camera body 14 to form a light sealed chamber adapted to facilitate film exposure and processing operations. At such times, a bail 32 pivotally connected to the back body member 16 serves to releasably attach the two body members 14 and 16 one to the other.

Reference is now made to FIGS. 2-4 of the drawings which more clearly depict the nature of the processing fluid spreading apparatus 12. As shown therein, this apparatus l2 basically comprises nine components, i.e., a pair of roller-type spreader elements 34 and 36, a pair of bearing blocks 38 and 40, a pair of substantially U- shaped load spring elements 42 and 44, a platform member 46, an edge control bar 48 and an edge control bar mounting spring 50.

The two spreader elements 34 and 36 are substantially identical in configuration in that each is provided with a sheet-contacting facing surface 52 and has end portions comprising a first cylindrical section 54 of reduced diameter and a second cylindrical section 56 of further reduced diameter. Provided in each bearing block 38 and 40 is a circular recess 58 configured to rotatably receive respective cylindrical sections 56 of the spreader element 36. Additionally, each bearing block 38 and 40 is provided with an elongated recess 60 configured to rotatably receive respective cylindrical sections 56 of the spreader element 34. In the illustrated embodiments, these recesses 58 and 60 extend entirely through respective blocks 38 and 40.

When rotatably mounted between the bearing blocks 38 and 40, the spreader element 36 is fixedly positioned against translational motion with respect to the bearing blocks. At the same time, the configuration of the elongated recesses 60 permit a limited amount of movement of the spreader element 34 towards and away from the spreader element 36. Respective circular recesses 58 and elongated recesses 60 are located in the bearing blocks 38 and 40 so as to establish a predetermined minimum spacing between the sheet contacting facing surfaces 52 of the spreader elements 34 and 36. This predetermined minimum spacing is selected to facilitate the initial introduction of the aforementioned leader associated with each film unit between the spreader elements 34 and 36, while at the same time assuring that the rollers 34 and 36 exert a compressive force on the pod of processing fluid 22 and the superposed imageqeceiving and imagerecording sheets 18 and 20 as those components of each film unit are advanced through the apparatus 12.

As will be subsequently explained in more detail, the U-shaped spring elements 42 and 44 are assembled into their respective operative positions with the bearing blocks 38 and 40 and the spreader elements 34 and 36 subsequent to the assembly of the spreader elementbearing block combination of the platform member 46. However, it should be noted at this time that each bearing block 38 and 40 is provided with a support surface 62 adapted to be engaged by one end 64 of a respective spring element 42 or 44. As best seen in FIG. 6 of the drawings, when each spring element 42 and 44 is mounted on its respective bearing block 38 or 40 with its ends 64 seated on a support surface 62, its other end 66 rests on a respective cylindrical section 56 of the spreader element 34. Thus, when these elements of the fluid spreading apparatus 12 are assembled in their operative positions, the U-shaped load spring elements 42 and 44 continually resiliently urge the spreader element 34 towards the spreader element 36. In order to provide a low friction bearing surface and to protect the spring elements 42 and 44 from attack by the processing fluid 22, these elements which are typically formed of spring steel, may be coated with a suitable material such as a fluoropolymer. The length of the elongated recesses 60 limit the distance which the spreader element 34 may be displaced away from the spreader element 36. This distance is selected so as to preclude an overstressing of the U-shaped load spring elements 42 and 44.

The length of the elongated facing surfaces 52 of the spreader elements 34 and 36 is selected to be substantially equivalent to the width of the photographic sheet materials 18 and 20. For instance, the aforementioned film packs marketed by the Polariod Corporation of Cambridge, Massachusetts include photographic sheet materials 18 and 20 having a width of approximately3 96 inches. Therefore, fluid spreading systems designed in accordance with the present invention for operation with such film packs would preferably employ spreader elements 34 and 36 having sheet contacting facing surfaces 52 on the order of 3 as inches in length. It will be noted that such an arrangement provides space between the ends of the facing surfaces 52 and adjacent sections of respective bearing blocks 38 and 40 substantially defined by the cylindrical sections 54 of the spreader elements 34 and 36. Any processing fluid which might escape from between the superposed longitudinal edges of the photographic sheet materials 18 and 20 as they pass through the spreader elements 34 and 36 will seep into these spaces. Thus, this fluid spreading apparatus 12 includes means for precluding such fluid seepage from contaminating the facing surfaces 52 of the spreader elements 34 and 36.

By way of example, the roller-type spreader elements 34 and 36 may be formed of a suitable stainless steel. Further, by way of example, the bearing blocks 38 and 40 may be formed (in an inexpensive injection molding process) of a suitable wear resistant, low friction polymeric material such as that sold by Celanese Plastics Company of Newark, New Jersey, a Division of Celanese Corporation, under their designation of Celanex 917.

The platform member 46 comprises a pair of spaced apart parallel walls 68 and 70 supported on, and extending from, a base plate 72. Means are provided on the platform member 46 in the form of ribs 74 and surfaces 76 for receiving the bearing blocks 38 and 40 with spreader elements 34 and 36 rotatably mounted therebetween. In this respect, these ribs 74 and surfaces 76 are dovetailed in two directions, i.e., from endto-end and from side-to-side. The edges and 77 of each bearing block 38 and 40 are dovetailed in a complementary manner. Thus, the bearing blocks 38 and 40 may be slideably inserted downwardly into the respective channels defined by the ribs 74 and surfaces 76 until the aforementioned complementary dovetailed surfaces engage one another. The terms downwardly," lowermost," etc., are used herein with respect to the orientation of various elements as depicted in the drawings for explanatory purposes only and are not to be construed in any limiting sense.

A pair of ribs 82 extending from the base plate 72 of the platform member 46 cooperate with adjacent portions of the base plate and respective walls 68 and 70 to define a pair of guide tracks which facilitate assembly operations in which the U-shaped load spring elements 42 and 44 are brought into their operative positions with respect to the bearing blocks 38 and 40 and the spreader elements 34 and 36. In this connection, it will first be noted that the spring elements 42 and 44 are rectangular in cross-section and that the aforementioned guide tracks are of a complementary configuration. During assembly operations, the legs of the U- shaped load spring elements 42 and 44 comprising the ends 64 and 66 are respectively. slideably inserted along the aforementioned guide tracks onto the platform member 46 in a forward direction, i.e., towards the rollers 34 and 36. Projections 84 and 86, comprising the dovetailed surfaces 76, respectively extend from the inside faces of the walls 68 and 70 and include cams or ramps 88 and 90. These ramps 88 and 90 are positioned to respectively engage ends 64 of spring elements 42 and 44 as those elements are slideably inserted into the platform member 46. They are further configured to urge the ends 64 of the springs 42 and 44 away from their ends 66 during such insertion processes to facilitate the positioning of the spring elements in operative relationship with their respective bearing blocks 38 and 40 and the spreader elements 34 and 36. At such time as the ends 67 of the spring elements 42 and 44 are urged away from the ends 66 of those spring elements by the ramps 88 and 90, their ends 64 are advanced onto the support surfaces 62 of respective bearing blocks 38 and 40. Provided on the support surface 62 of each bearing block 38 and 41B is a key or detent 92 which seats in a complementarily configured recess 94 of its respective spring element 42 or 44 once that spring element is mounted on its associated bearing block in operative relationship with respect thereto and the spreader elements 34 and 36. Thus, the fluid spreading apparatus 12 includes means for releasably retaining the spring elements 42 and 44 in their operative positions. It will be recognized that, as an alternate arrangement, the keys or detents may be provided on the spring elements 42 and 44 with the recesses being provided on the bearing blocks 38 and 40. Still further, if desired the detents may alternately be formed as part of the projections 84 and 86.

Tabs 96 and 98, respectively extending from the inside faces of the walls 68 and 70, cooperate with the ribs 82 and the adjacent sections of those walls and the base plate 72 to fixedly retain the spring elements 42 and 44 on the platform member 46. Forward movement of the spring elements 42 and 44 along the platform member 46 is limited by tabs 100 and 102 respectively extending from the inside faces of the walls 68 and 70.

The platform member 46 also includes a bridge 104 which extends between the inside faces of the projections 84 and 86. This bridge 104 serves several functions with respect to the advancement of the film units through the fluid spreading apparatus 12. Along these lines, it should first be noted that when the processing fluid spreading device 12 is mounted in the cameras back body member 16, the pressure-generating gap 106 defined by the juxtaposed facing surfaces 52 of the spreader elements 34 and 36 is aligned with an elongated exit port 108 (See FIG. formed through the adjacent wall 110 of the back body member. Also, when the back body member 16 is closed against the main camera body 14, its upper edge 112 cooperates with the main camera bodys ribs 114 and lip 116 to define a channel 118 providing additional access into the camera 10.

Asis'well known, when a film pack of the type indicated is mounted in the camera and the back body member 16 thereof closed thereover, the tabs (not shown) attached to the film units extend through this channel 118. By drawing on one of these tabs, after making an exposure, a leader attached to the associated film unit is advanced into the pressure-generating gap 106 of the fluid spreading device 12 so as to protrude through the camera's elongated exit port 108. The lower edge of the bridge 104 comprises a tapered surface 120 which serves to guide operator leader associated with each film unit into the pressure-generating gap 106 and through the exit port 108 as the operatpr pulls on the tab associated with that particular film unit. Once the leader has been introduced under the bridge 104, the bridge serves the additional function of maintaining proper alignment of the film unit as its leader is advanced into the pressure-generating gap 106 in the process of pulling the aforementioned tab, i.e., it precludes the leader from following the tab through the channel 118, and facilitates the striping of the tab from the film unit. It should further be noted at this time that the platform member 46 includes a support surface 122 which also serves to guide and support the film units as they are advanced from the aforementioned film pack through the fluid spreading apparatus 12.

As best seen in FIG. 2 of the drawings, the edge control bar 48 includes a pair of parallel spaced apart fish hooks 124 which facilitate the mounting of that element on the platform member 46. This edge control bar 48 may be formed of any suitable material, such as a fiberglass reinforced nylon, so as to provide its fish hooks 124 with a limited yieldably resilient characteristic. In other words, so that they may be resiliently displaced toward one another. The specially configured spring 50 facilitates the resilient mounting of the edge control bar 48 on the platform member 46. In this connection, a bracket 126 provided with an aprerture 128 extends from the lower face of the platform member 46 and forms a part thereof. The spring 50 is positioned on the edge control bar 48 with its offset section 130" seated against the ends 132 of the fish books 124 and with its upturned ends 134 respectively positioned in recesses 136 provided in the lower face of the edge control bar. This edge control bar 48 spring 50 combination is then mounted on the platform member 46 by inserting the fish hooks 124 and the adjacent sections of the spring 50 through the aperture 128 of the bracket 126. In this process, the bracket 126 causes the fish hooks 124 to be deflected towards one another until their enlarged head portions 138 have cleared the bracket 126, at which time they return to their original positions with respect to one another to releasably retain the edge control bar and spring 50 on the platform member 46. Once the edge control bar 48 has been so mounted on the platform member 46, the spring 50 serves to resiliently urge it towards the bridge 104. Fingers 140, forming part of the edge control bar 48, are spaced apart a carefully predetermined distance so as to press respective longitudinal edge portions of the superposed sheets 18 and 20 against adjacent portions 142 of the bridge 104 as those sheets are progressively advanced through the fluid spreading apparatus 12. Thus, the edge control bar 48 and the bridge 104 cooperate to preclude processing fluid 22 from escaping from between the longitudinal edge portions of the superposed sheet materials 18 and 20 as each film unit is advanced through the apparatus 12 in the course of film processing operations. By way of example, the edge control bar 48 may be formed of any suitable material such as a fiberglass reinforced nylon.

Extending from the end of the support surface 122 so as to form a part of the platform member 46 is a spring latch 144. This latch 144 cooperates with a brace 146 normally provided in the types of cameras indicated, to releasably retain the fluid spreading apparatus 12 in the camera 10. It should be noted that the normal function of the brace 146 in such cameras is to engage a resilient finger provided on each film pack to urge same into contact with respective image-receiving sheets 18 of the various film units. In this manner, as an operator withdraws a leader from the camera 10 through its elongated exit port 108, the aforementioned resilient finger precludes advancement of the associated imagereceiving sheet 18 from the film pack until such time as the leader and mask of that film unit have been unfolded and drawn taut. In the present arrangement, the brace 146 serves the same function. However, as indicated, it addditionally serves to cooperate with the spring latch 144 of the fluid spreading apparatus 12 to releasably retain that apparatus in the camera 10. The outside faces of the platform members walls 68 and 70, the front edges 148 and 150, respectively of those walls and the base plate 72 serve to accurately align and substantially fixedly position the fluid spreading apparatus 12 within the camera 10. As the apparatus 12 is inserted into the camera 10, the spring latch 144 is compressed by the brace 146 thereby resiliently urging the front edges 148 and 150, respectively, of the platform members walls 68 and 70 against the inside face of the cameras wall 110. The specially configured projection 151 and cut-out 153 provided on the base plate 72 cooperate with complementary indicia on the inside face of the cameras wall 155 to indicate to the operator the proper alignment of the spreading apparatus 12 within the camera 10. This arrangement precludes the operator from attempting to improperly insert or from jamming the apparatus into the camera.

The spring latch 144 includes a pair of anns 152 respectively terminating in flange portions 156 and 158 positioned in recesses 160 and 162 of the platform member 46 (See FIG. 2). Thus adjacent sections of the platform member 46 serve as stops to limit the movement of the spring latch 144 and preclude accidental ovcrstressing of same.

Most advantageously, the platform member 46 including the aforementioned means for receiving the bearing blocks 38 and 40; the projections 84 and 86; the ribs 82; the tabs 96, 98, 100 and 102; the bracket 126; the bridge 104; the support surface 122; and the spring latch 144 may be formed as an integral unit of a suitable plastic material, such as a fiberglass reinforced polycarbonate, in an inexpensive injection molding process. To provide the latch 144 with its necessary resilient characteristic, a transverse section 164 thereof is provided with a reduced cross-sectional dimension during the molding operation.

It will be apparent to those skilled in the art that the fluid spreading apparatus 12 readily lends itself to lowcost, automated, high-volume fabrication and assembly techniques. Assembly operations comprise the following steps:

1. The spring 50 is mounted on the control bar 48 and this spring-control bar combination is mounted on the platform member 46 by inserting the fish hooks 124 and adjacent sections of the spring 50 through the bracket 126.

2. The roller-type spreader elements 34 and 36 are mounted between the bearing blocks 38 and 40.

3. The bearing block-spreader element combination is mounted on the platform member 46 by slideably inserting the bearing blocks 38 and 40 downwardly into the respective bearing block receiving means provided on the platform member.

4. The U-shaped spring elements 42 and 44 are slideably inserted onto the platform member 46 in a forward direction along their respective guide tracks until they are in operable relationship with their associated bearing blocks 38 and 40 and the spreader elements 34 and 36.

It is important to note that the bearing block-spreader element combination is slideably inserted onto the platform member 46 in a first direction and the load spring elements 42 and 44 are slideably inserted onto that platform member in a direction substantially normal to the first mentioned direction. Once the load spring elements 42 and 44 are in operative position with respect to the bearing blocks 38 and 40 and the spreader elements 34 and 36, they are releasably retained in that position by the detents 92.

This assembly technique contrasts significantly with that associated with the fluid spreading apparatus originally marketed in the aforementioned Colorpack II" cameras. That prior art fluid spreading system basically comprises a pair of sheet metal spreader elements connected together by a pair of U-shaped springs, respective ends of which are welded to the spreader elements. Obviously, such assembly techniques require some degree of close tolerance work to maintain proper sheetcontacting facing surface configurations and alignment. Such assembly techniques have resulted in a significant scrappage factor, increasing the actual cost of producing satisfactory spreader systems. Consequently, while the roller-type spreader elements 34 and 36 of the present invention are somewhat more expensive than their sheet metal counterparts employed in the prior art fluid spreading apparatus, it has been found that the assembly operations associated with the present invention permits such fluid spreading apparatus to be produced in large quantities at a cost actually lower than that associated with producing the prior art device.

A major factor contributing to the low cost of the roller-type spreading apparatus 12 of the present invention is the unique platform member 46. As previously indicated, this platform member 46 serves a plurality of functions. Yet it comprises an integral piece of molded plastic material that may be very inexpensively produced in an injection molding process.

One of the advantages of the present invention is that it provides a roller-type spreader system which may be quickly inserted into and removed from a camera to facilitate spreader element cleaning operations and/or replacement operations. In the hereinbefore described embodiment of the invention, respective cylindrical sections 56 are continually engaged by load spring elements 42 and 44. Thus, when the fluid spreading apparatus 12 is removed from the camera 10 for cleaning purposes, there is some resistance to the rotation of the spreader element 34 while the spreader element 36 may be freely rotated. In an alternate embodiment depicted in FIG. 7, opposite ends of the roller 34 are rotatably supported in elongated recesses 166 of the bearing blocks 38 and 40. These elongated recesses 166 are configured such that the adjacent ends of the spring elements 42 and 44 are initially seated on sup port surfaces 168 of the bearing blocks. More specifically, at such times there is a small space separating the spring elements 42 and 44 from the spreader element 34. Thus, in this alternate arrangement, the spreader element 34 may be freely rotated in the bearing blocks 38 and 40 to facilitate cleaning operations.

Those familiar with the photographic arts will readily appreciate the novel and highly unique advantages of this invention. Most importantly, an inexpensive and improved roller-type fluid spreading apparatus is'provided which may be readily inserted into and removed from a camera as an integral assembly. Further, this fluid spreading apparatus may be used to replace similar apparatus currently provided in commercially available cameras without otherwise altering those cameras in any manner.

This invention may be practiced or embodied in still other ways without departing from the spirit or essential character thereof. The preferred embodiments described herein are therefore illustrative and not restrictive, the scope of the invention being indicated by the appended claims and all variations which come within the meaning of the claims are intended to be embraced therein.

What is claimed is:

l. Photographic apparatus for spreading a processing fluid between a pair of sheet materials comprising:

a pair of elongated spreader elements;

1 a pair of spaced apart bearing blocks including first means for rotatably mounting said pair of spreader elements therebetween in substantially parallel alignment and for establishing a predetermined minimum spacing between said spreader elements, both of said bearing blocks being structured to facilitate the displacement of at least one of said spreader elements away from the other of said spreader elements thereby increasing the spacing between said spreader elements a distance greater than said predetermined minimum spacing;

second means for yieldably urging said one spreader element towards said other spreader element at least when the spacing between said spreader elements is increased a distance greater than said predetermined minimum spacing, said second means including a pair of spring elements, each of said spring elements being mounted on one of said bearing blocks; and

platform member including means for receiving each said bearing block and means for guiding each said spring element into its operative position with its respective said bearing block and said spreader elements during assembly of said apparatus.

2. The apparatus of claim 1 wherein each said spring element comprises a substantially U-shaped spring element and wherein said guiding means includes means for urging the two legs of each said U-shaped spring element apart as it is brought into operative position with its respective said bearing block and said spreader elements during assembly of said apparatus.

3. The apparatus of claim 2 wherein each said spring urging means comprises a ramp.

4. The apparatus of claim 2 additionally comprising key means for releasably locking each said U-shaped spring element in its said operative position.

5. The apparatus of claim 2 additionally comprising complementary recess and detent means formed on each said spring element and another member of said apparatus to releasably lock each said U-shaped spring element in its said operative position.

6. The apparatus of claim 1 wherein said platform member comprises a single piece of molded material.

7. Photographic apparatus for spreading a processing fluid betweena pair of sheet materials comprising:

a pair of elongated spreader elements;

a pair of spaced apart bearing blocks including first means for rotatably mounting said pair of spreader elements therebetween in substantially parallel alignment and for establishing a predetermined minimum spacing between said spreader elements, both of said bearing blocks being structured to facilitate the displacement of at least one of said spreader elements away from the other of said 5 spreader elements thereby increasing the spacing between said spreader elements a distance greater than said predetermined minimum spacing; second means for yieldably urging said one spreader element toward said other spreader element at least when the spacing between said spreader elements is increased a distance greater than said predetermined minimum spacing, said second means including a pair of spring elements, each of said spring elements being mounted on one of said bearing blocks; and a platform member comprising means for guiding each said spring element into its operative position with its respective said bearing block and said spreader elements during assembly of said apparatus and for retaining each said spring element in its said operative position. 8. The apparatus of claim 7 wherein each said spring element is rectangular incross-section and said guiding and retaining means comprises a guide track of com plementary configuration to said cross-sectional configuration of each said spring element.

9. Photographic apparatus for spreading processing fluid between a pair of sheet materials comprising:

a pair of elongated spreader elements;

an edge control member;

spring means connected to said edge control member;

means for mounting said spreader elements for rotation about parallel axes of rotation and for displacement of at least one of said pair of spreader elements away from the other said spreader element; and

means for resiliently urging said one spreader element toward said other spreader element, said mounting means comprising a platform member formed of a single piece of material and including means for guiding such sheet materials between said spreader elements, means for receiving and mounting said edge control member and said spring means with said edge control member disposed in juxtaposition with said sheet material guiding means and being resiliently urged thereagainst by said spring means and means for retaining said resiliently urging means in operative position with respect to said spreader elements.

10. The apparatus of claim 9 wherein said resiliently urging means comprises at least one substantially U- shaped spring element.

11. Photographic apparatus for spreading a processing fluid between a pair of sheet materials comprising means for rotatably mounting a pair of roller-type spreader elements in juxtaposition with at least one of such spreader elements mounted for a limited amount of displacement away from the other, means for resiliently urging such first spreader element towards the other, and a platform member formed of a single piece of material, said platform member including means to receive said mounting means and means to receive said resiliently urging means including means for guiding said spreader element urging means into its operative resiliently urging means, said means for receiving said position with such spreader elements during assembly of said apparatus.

12. The apparatus of claim 11 wherein said resiliently urging means comprises at least one substantially U- shaped spring element and said means for guiding said U-shaped spring element into its operative position with such spreader elements includes a ramp positioned to urge the two legs of said Ushaped spring element apart as it is brought into its operative position with such spreader elements.

13. Photographic apparatus for spreading a processing fluid between a pair of sheet materials comprising means for rotatably mounting a pair of roller-type spreader elements in juxtaposition; and edge control bar; spring means; and a platform member formed of a single piece of material, said platform member including means for guiding such sheet materials towards such spreader elements, means for receiving said spreader element mounting means, means for receiving both said spring means and said edge control bar with said spring means resiliently urging said edge control bar towards said sheet material guiding means to cooperate therewith to preclude such fluid escaping from between the longitudinal edges of such sheet materials in advance of such spreader elements as such sheet materials are advanced therebetween.

l4. Photographic apparatus for spreading a processing fluid between a pair of sheet materials comprising:

a pair of elongated spreader elements;

a pair of spaced apart bearing blocks including first means for rotatably mounting said pair of spreader elements lengthwise therebetween in substantially parallel alignment, both said bearing blocks being structured to facilitate the displacement of at least one of said spreader elements away from the other of said spreader elements;

second means for yieldably urging said one spreader element towards said other spreader element at least when said one spreader element is displaced away from said other spreader element; and platform member including means for receiving said bearing blocks thereon in the process of effecting a sliding motion between said bearing blocks and said platform member in a first direction with respect to said platform member and means for receiving said second means into operable position with respect to said bearing blocks and said spreader elements in a second direction with respect to said platform member differing from said first direction, said second means serving to releasably retain the assembly of said spreader elements, said bearing blocks, said platform member and said second means together at such time.

15. The apparatus of claim 14 wherein said orientation of said first direction with respect to said second direction is on the order of 90.

16. The apparatus of claim 14 wherein said second means comprises at least one substantially U-shaped spring element.

17. The apparatus of claim 14 wherein said second means and said bearing blocks comprise at least one recess and a complementary detent located to engage one another when said second means is in its said operative position with respect to said spreader elements and said bearing blocks.

l8. Photographic apparatus for spreading a processing fluid between a pair of sheet materials comprising:

a pair of elongated spreader elements;

a pair of spaced apart bearing blocks including first means for rotatably mounting said pair of spreader elements therebetween in substantially parallel alignment and for establishing a predetermined minimum spacing between said spreader elements, both of said bearing blocks being structured to facilitate the displacement of at least one of said spreader elements away from the other said spreader element thereby increasing the spacing between said spreader elements a distance greater than said predetermined minimum spacing;

a base plate;

second means extending from said base plate for receiving said bearing blocks;

a pair of substantially U-shaped spring elements;

third means connected to said base plate for guiding each said U-shaped spring element into operative position with a respective said bearing block and said spreader elements during assmebly of said apparatus; and

key means for releasably retaining said U-shaped spring elements in their operative positions.

19. The apparatus of claim 18 wherein said third means includes ramp means for spreading opposite ends of each said spring element apart as it is assemled into its said operative position.

20. The apparatusof claim 18 additionally including fourth means for guiding such sheet materials between said spreader elements as they are advanced through said apparatus and said base plate, said second means, said third means and said fourth means are formed of a single piece of molded material.

21. The apparatus of claim 20 additionally including an edge control bar, means formed integrally with said single piece of molded material for mounting said edge control bar thereon in juxtaposed relationship to said fourth means and means mounted on said single piece of molded material for resiliently urging said edge control bar towards said fourth means.

22. Photographic apparatus for spreading a processing fluid between a pair of sheet materials comprising:

a pair of elongated spreader elements, each said spreader element having circular end portions of a given diameter;

a pair of spring elements; and

a pair of spaced apart bearing blocks for rotatably mounting said pair of spreader elements lengthwise therebetween in substantially parallel alignment, each said bearing block including a pair of spaced apart recesses, one of each said pair of recesses being circular in configuration to fixedly receive one said end portion of one said spreader element against translational motion while facilitating rotational movement thereof and the other of said recesses comprising an open ended elongated slot to receive one said end portion of said other spreader element to facilitate both rotational movement thereof and translational motion thereof with respect to said one end portion of said one spreader element disposed within said circular recess, said circular recess being spaced a predetermined distance from said elongated slot to establish a predetermined minimum spacing between said spreader elements, each said bearing block including means for suporting one end of one said spring element with the other end of said one spring element overspring element is generally U-shaped.

24. The apparatus of claim 22 wherein complementary locking means are respectively formed on each said bearing block and said spring element supported thereon. 

1. Photographic apparatus for spreading a processing fluid between a pair of sheet materials comprising: a pair of elongated spreader elements; a pair of spaced apart bearing blocks including first means for rotatably mounting said pair of spreader elements therebetween in substantially parallel alignment and for establishing a predetermined minimum spacing between said spreader elements, both of said bearing blocks being structured to facilitate the displacement of at least one of said spreader elements away from the other of said spreader elements thereby increasing the spacing between said spreader elements a distance greater than said predetermined minimum spacing; second means for yieldably urging said one spreader element towards said other spreader element at least when the spacing between said spreader elements is increased a distance greater than said predetermined minimum spacing, said second means including a pair of spring elements, each of said spring elements being mounted on one of said bearing blocks; and a platform member including means for receiving each said bearing block and means for guiding each said spring element into its operative position with its respective said bearing block and said spreader elements during assembly of said apparatus.
 2. The apparatus of claim 1 wherein each said spring element comprises a substantially U-shaped spring element and wherein said guiding means includes means for urging the two legs of each said U-shaped spring element apart as it is brought into operative position with its respective said bearing block and said spreader elements during assembly of said apparatus.
 3. The apparatus of claim 2 wherein each said spring urging means comprises a ramp.
 4. The apparatus of claim 2 additionally comprising key means for releasably locking each said U-shaped spring element in its said operative position.
 5. The apparatus of claim 2 additionally comprising complementary recess and detent means formed on each said spring element and another member of said apparatus to releasably lock each said U-shaped spring element in its said operative position.
 6. The apparatus of claim 1 wherein said platform member comprises a single piece of molded material.
 7. Photographic apparatus for spreading a processing fluid between a pair of sheet materials comprising: a pair of elongated spreader elements; a pair of spaced apart bearing blocks including first means for rotatably mounting said pair of spreader elements therebetween in substantially parallel alignment and for establishing a predetermined minimum spacing between said spreader elements, both of said bearing blocks being structured to facilitate the displacement of at least one of said spreader elements away from the other of said spreader elements thereby increasing the spacing between said spreader elements a distance greater than said predetermined minimum spacing; second means for yieldably urging said one spreader element toward said other spreader element at least when the spacing between said spreader elements is increased a distance greater than said predetermined minimum spacing, said second means including a pair of spring elements, each of said spring elements being mounted on one of said bearing blocks; and a platform member comprising means for guiding each said spring element into its operative position with its respective said bearing block and said spreader elements during assembly of said apparatus and for retaining each said spring element in its said operative position.
 8. The apparatus of claim 7 wherein each said spring element is rectangular in cross-section and said guiding and retaining means comprises a guide track of complementary configuration to said cross-sectional configuration of each said spring element.
 9. Photographic apparatus for spreading processing fluid between a pair of sheet materials comprising: a pair of elongated spreader elements; an edge control member; spring means connected to said edge control member; means for mounting said spreader elements for rotation about parallel axes of rotation and for displacement of at least one of said pair of spreader elements away from the other said spreader element; and means for resiliently urging said one spreader element toward said other spreader element, said mounting means comprising a platform member formed of a single piece of material and including means for guiding such sheet materials between said spreader elements, means for receiving and mounting said edge control member and said spring means with said edge control member disposed in juxtaposition with said sheet material guiding means and being resiliently urged thereagainst by said spring means and means for retaining said resiliently urging means in operative position with respect to said spreader elements.
 10. The apparatus of claim 9 wherein said resiliently urging means comprises at least one substantially U-shaped spring element.
 11. Photographic apparatus for spreading a processing fluid between a pair of sheet materials comprising means for rotatably mounting a pair of roller-type spreader elements in juxtaposition with at least one of such spreader elements mounted for a limited amount of displacement away from the other, means for resiliently urging such first spreader element towards the other, and a platform member formed of a single piece of material, said platform member including means to receive said mounting means and means to receive said resiliently urging means, said means for receiving said resiliently urging means including means for guiding said spreader element urging means into its operative position with such spreader elements during assembly of said apparatus.
 12. The apparatus of claim 11 wherein said resiliently urging means comprises at least one substantially U-shaped spring element and said means for guiding said U-shaped spring element into its operative position with such spreader elements includes a ramp positioned to urge the two legs of said U-shaped spring element apart as it is brought into its operative position with such spreader elements.
 13. Photographic apparatus for spreading a processing fluid between a pair of sheet materials comprising means for rotatably mounting a pair of roller-type spreader elements in juxtaposition; and edge control bar; spring means; and a platform member formed of a single piece of material, said platform member including means for guiding such sheet materials towards such spreader elements, means for receiving said spreader element mounting means, means for receiving both said spring means and said edge control bar with said spring means resiliently urging said edge control bar towards said sheet material guiding meaNs to cooperate therewith to preclude such fluid escaping from between the longitudinal edges of such sheet materials in advance of such spreader elements as such sheet materials are advanced therebetween.
 14. Photographic apparatus for spreading a processing fluid between a pair of sheet materials comprising: a pair of elongated spreader elements; a pair of spaced apart bearing blocks including first means for rotatably mounting said pair of spreader elements lengthwise therebetween in substantially parallel alignment, both said bearing blocks being structured to facilitate the displacement of at least one of said spreader elements away from the other of said spreader elements; second means for yieldably urging said one spreader element towards said other spreader element at least when said one spreader element is displaced away from said other spreader element; and a platform member including means for receiving said bearing blocks thereon in the process of effecting a sliding motion between said bearing blocks and said platform member in a first direction with respect to said platform member and means for receiving said second means into operable position with respect to said bearing blocks and said spreader elements in a second direction with respect to said platform member differing from said first direction, said second means serving to releasably retain the assembly of said spreader elements, said bearing blocks, said platform member and said second means together at such time.
 15. The apparatus of claim 14 wherein said orientation of said first direction with respect to said second direction is on the order of 90*.
 16. The apparatus of claim 14 wherein said second means comprises at least one substantially U-shaped spring element.
 17. The apparatus of claim 14 wherein said second means and said bearing blocks comprise at least one recess and a complementary detent located to engage one another when said second means is in its said operative position with respect to said spreader elements and said bearing blocks.
 18. Photographic apparatus for spreading a processing fluid between a pair of sheet materials comprising: a pair of elongated spreader elements; a pair of spaced apart bearing blocks including first means for rotatably mounting said pair of spreader elements therebetween in substantially parallel alignment and for establishing a predetermined minimum spacing between said spreader elements, both of said bearing blocks being structured to facilitate the displacement of at least one of said spreader elements away from the other said spreader element thereby increasing the spacing between said spreader elements a distance greater than said predetermined minimum spacing; a base plate; second means extending from said base plate for receiving said bearing blocks; a pair of substantially U-shaped spring elements; third means connected to said base plate for guiding each said U-shaped spring element into operative position with a respective said bearing block and said spreader elements during assmebly of said apparatus; and key means for releasably retaining said U-shaped spring elements in their operative positions.
 19. The apparatus of claim 18 wherein said third means includes ramp means for spreading opposite ends of each said spring element apart as it is assemled into its said operative position.
 20. The apparatus of claim 18 additionally including fourth means for guiding such sheet materials between said spreader elements as they are advanced through said apparatus and said base plate, said second means, said third means and said fourth means are formed of a single piece of molded material.
 21. The apparatus of claim 20 additionally including an edge control bar, means formed integrally with said single piece of molded material for mounting said edge control bar thereon in juxtaposed relationship to said fourth means and means mounted on said single piece of molded materIal for resiliently urging said edge control bar towards said fourth means.
 22. Photographic apparatus for spreading a processing fluid between a pair of sheet materials comprising: a pair of elongated spreader elements, each said spreader element having circular end portions of a given diameter; a pair of spring elements; and a pair of spaced apart bearing blocks for rotatably mounting said pair of spreader elements lengthwise therebetween in substantially parallel alignment, each said bearing block including a pair of spaced apart recesses, one of each said pair of recesses being circular in configuration to fixedly receive one said end portion of one said spreader element against translational motion while facilitating rotational movement thereof and the other of said recesses comprising an open ended elongated slot to receive one said end portion of said other spreader element to facilitate both rotational movement thereof and translational motion thereof with respect to said one end portion of said one spreader element disposed within said circular recess, said circular recess being spaced a predetermined distance from said elongated slot to establish a predetermined minimum spacing between said spreader elements, each said bearing block including means for suporting one end of one said spring element with the other end of said one spring element overlying the opened end of said elongated slot to be engaged by said other spreader element at least when said other spreader element is displaced away from said one spreader element a distance greater than said predetermined minimum spacing.
 23. The apparatus of claim 22 wherein each said spring element is generally U-shaped.
 24. The apparatus of claim 22 wherein complementary locking means are respectively formed on each said bearing block and said spring element supported thereon. 